Amateur Coolant Level Question (1 Viewer)

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I'm in the process of identifying a small/slow leak in my '99 LC, so I've been regularly checking fluids. Yesterday, after driving for about 2 hours, I was checking fluids and the coolant level was about 2 inches above the low mark.

Today, after the LC sitting overnight, I checked and it was well below the low mark with just a small portion of coolant in the reservoir (wasn't bone dry, but was definitely low).

Two questions:
1. Should I add coolant? I'm thinking yes, even though I know levels fluctuate based on engine temp.
2. If so, and I don't know what type of coolant is in there now (appears to be greenish), is it ok to mix different types?

Thanks for the help!
 
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When engine is cold, it'll draw in the coolant back into the system, that's why the full mark is the midway point of the reservoir because fluid level will fluctuate. Add Toyota pink to the system when engine is cold, up to the full mark.
 

94SRUNNER

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Make sure that if you add coolant to the system, that you try and match the coolant type. DO NOT MIX a green coolant with a Toyota Pink or Red.

And I would start looking for a leaking connection somewhere in the system. The heater T’s and the thermostat housing are common failure points, but it could be anywhere.
 
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Mark sure that if you add coolant to the system, that you try and match the coolant type. DO NOT MIX a green coolant with a Toyota Pink or Red.

That was my concern - what’s the reason for this?

It’s headed into the specialist on Tuesday, so to be safe I’ll have him take care of it.
 

94SRUNNER

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That was my concern - what’s the reason for this?

It’s headed into the specialist on Tuesday, so to be safe I’ll have him take care of it.

The chemistry of the two types are different and can cause a sludge to build up in the system.
 
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The chemistry of the two types are different and can cause a sludge to build up in the system.

Fair enough!

I did read on several of the brands that they claim they can be mixed with whatever you have, but I’d prefer to play it safe.
 

94SRUNNER

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If you are in a warmer climate that is not prone to freezing then you can add distilled water to the system.
 
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When you find and fix the leak then get rid of the green coolant and add the proper Toyota coolant. It has a different chemistry that is compatible with the materials used in the system.
 

abuck99

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If you are in a warmer climate that is not prone to freezing then you can add distilled water to the system.

In an emergency or short term situation this is ok but its important to also point out that diluting the 50/50 mix with (water) will also dilute additives ( anti-corrosion, lubricating properties for waterpump, pH stabilizer) in the coolant that protects the radiator, heater core, cooling passages etc. from build up.
 

94SRUNNER

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In an emergency or short term situation this is ok but its important to also point out that diluting the 50/50 mix with (water) will also dilute additives ( anti-corrosion, lubricating properties for waterpump, pH stabilizer) in the coolant that protects the radiator, heater core, cooling passages etc. from build up.

Great point!

To the OP. Once you nail down the coolant level issue. Schedule yourself some time to perform a coolant system refresh.
 

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